The present invention relates to a drive device of an inboard-and-out-board propulsion machine to be mounted onto a boat like a yacht, especially improved in its maintenance efficiency.
Conventionally, there is a well-known inboard-and-outboard propulsion machine for a boat like a yacht, such that a drive unit connected to an engine is disposed through an opening of a hull of the boat so as to make a lower unit of the drive unit project in water, and the drive unit is provided therein with a substantially vertical drive shaft, as disclosed in Japanese Patent Hei.1-34837, for example.
The inboard-and-outboard propulsion machine comprises an upper unit disposed in the hull to be connected to the engine. In the upper unit is disposed a drive gear unit for transmitting power of the engine to the drive shaft through a clutch.
The propulsion machine is usually installed in the state that the engine is disposed in front of the drive unit. However, it is so constructed that the upper unit can be rotated at a 180xc2x0 in relation to the lower unit for enabling the engine to be disposed behind the drive unit in correspondence to the structure of the hull and so on, as disclosed in Japanese Utility Model Sho.62-21518, for example.
At the lower end of the drive unit projecting outwardly from the hull is provided an oil-drain outlet from which old lubricating oil circulated in the drive unit is drained out so as to be exchanged for new lubricating oil.
However, the drive unit must be separated from the engine because the drive gear unit for its maintenance, because the drive gear unit, the clutch and the like are assembled together in the drive unit of the conventional propulsion machine. Therefore, the maintenance of the drive unit is complicated and it is difficult to be performed on the sea.
Furthermore, the exchange of lubricating oil in the drive unit is complicated because it requires the hull to be lifted so as to drain the lubricating oil from the oil-draining opening provided at the lower end of the drive unit.
Some ports or harbors are equipped with no lifting device for a boat like a yacht, where the exchange of lubricating oil is impossible.
For being applied to an inboard-and-outboard propulsion machine including a drive unit mounted through an opening of a hull and brought into connection with an engine so that a lower unit serving as a lower part of the drive unit projects from the opening into water and a drive shaft is substantially vertically disposed in the drive unit, according to the present invention, a drive gear unit meshing with a follower gear disposed on an upper portion of the drive shaft is slidable in perpendicular to the drive shaft, and the drive gear unit is operable for its sliding movement from the outside of an upper unit serving as an upper part of the drive unit disposed in the hull. Therefore, a clutch shaft and the like can be removed from the upper unit disposed in the hull for maintenance of the interior of the upper unit while the engine and the drive unit are connected with each other. In other words, while the engine and the drive unit are left on the hull, the maintenance can be performed easily even on the sea.
Also, for an inboard-and-outboard propulsion machine which is similar with the same-mentioned, according to the present invention, an oil-circulation passage for circulating lubricating oil in the drive unit and an oil-drain passage for draining lubricating oil outward from the drive unit communicate with each other, and an oil-drain outlet of the oil-drain passage is provided at an upper unit serving as an upper part of the drive unit disposed in the hull. Therefore, the lubricating oil to the very bottom drop in the drive unit can be drained out from the oil-drain outlet, thereby enhancing the efficiency of its maintenance. Also, the lubricating oil in the drive unit can be exchanged on the sea without lifting the boat at a port or a harbor.
Also, for a inboard-and-outboard propulsion machine which is similar with the same-mentioned, according to the present invention, an upper unit serving as an upper part of said drive unit disposed in said hull can be rotated for its mounting at an approximate 180xc2x0 phase with respect to said lower unit, an oil-circulation passage for circulating lubricating oil in said drive unit and an oil-drain passage for draining lubricating oil outward from said drive unit communicate with each other, an oil-drain outlet of said oil-drain passage is provided at said upper unit disposed in said hull, a communication passage is disposed at a joint portion between said upper unit and said lower unit so that an upper oil-circulation passage and an upper oil-drain passage of said upper unit are respectively brought into communication with a lower oil-circulation passage and a lower oil-drain passage through said communication passage, said communication passage includes a pair of mounting portions apart from each other at an approximate 180xc2x0 phase, and a passage shutter for dividing said communication passage into two parts is selectively mounted to one of said pair of mounting portions, thereby ensuring the communication between said upper and lower oil-circulation passages and the communication between said upper and lower oil-drain passages in whichever direction said upper unit is mounted. Therefore, whichever the upper unit is directed, lubricating oil can be circulated through the same passages in the drive unit, and drained from the same oil-drain outlet, thereby enhancing the efficiency of maintenance of the drive unit so that the lubricating oil can be exchanged on the sea.